Energy transfer from Gd3+ to Eu3+ in silica xerogels

Luminescent xerogels co-doped with Gd3+ and Eu3+ ions were obtained in silica matrix. The effect of gadolinium ions on visible emission of europium ions in prepared xerogels has been studied. Spectroscopic parameters for Eu3+ and Gd3+ ions were determined based on excitation and emission measurements as well as luminescence decay analysis. The luminescence decay for the 5D0 level of Eu3+ ions in sample after excitation at 273 nm is almost twice as long in comparison to excitation at 393 nm. The luminescence intensity coefficient R (Eu3+) was calculated, and it was found that ratio of the intensity of red to orange line clearly depends on the excitation parameters. Based on these spectroscopic parameters the energy transfer process from Gd3+ to Eu3+ ions has been confirmed.